Addiction Psychiatry: Dependence, Withdrawal, and Harm Reduction
Core concepts
Know the dependence syndrome (compulsion, tolerance, withdrawal, salience, loss of control, persistence despite harm). Understand withdrawal syndromes: alcohol (tremor, seizures, delirium tremens), opioids (autonomic symptoms, cravings), benzodiazepines (rebound anxiety, seizures), and stimulants (dysphoria, fatigue). Know substitution therapies (methadone, buprenorphine, nicotine replacement) and the principles of motivational interviewing and harm reduction.
Traps
Questions test whether a presentation is intoxication, withdrawal, or a primary psychiatric disorder. Beware attributing psychiatric symptoms to substances without considering dual diagnosis. Thiamine supplementation in alcohol use is essential to prevent Wernicke's encephalopathy.
Worked example
A patient with heavy alcohol use presents with confusion, ataxia, and ophthalmoplegia. The rule of thumb: give parenteral thiamine before glucose in any at-risk patient; Wernicke's encephalopathy is a medical emergency.
Key points for revision
Dependence is a syndrome, not simply quantity of use.